Exploding trees: the winter phenomenon behind frost cracks
When temperatures drop suddenly, trapped water can freeze and expand, splitting trunks with a gunshot-like sound
TL;DR
- Trees use bark for insulation and cellular changes (dehydration, increased sugar) to prevent freezing.
- Sudden cold can cause water in the outer wood to freeze and expand, creating pressure.
- This pressure can lead to frost cracks, which are deep vertical splits in the tree, sometimes accompanied by an explosive sound.
- Frost cracking is more likely on sunny days when warm bark rapidly cools at night.
- Frost cracks can harm trees by making them vulnerable to insects and fungi.
- Exploding trees are not dangerous to bystanders, but the sounds can be unsettling.